michael@0: /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
michael@0:  * vim: set ts=8 sts=4 et sw=4 tw=99:
michael@0:  * This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef jspropertytree_h
michael@0: #define jspropertytree_h
michael@0: 
michael@0: #include "jsalloc.h"
michael@0: #include "jspubtd.h"
michael@0: 
michael@0: #include "js/HashTable.h"
michael@0: 
michael@0: namespace js {
michael@0: 
michael@0: class Shape;
michael@0: struct StackShape;
michael@0: 
michael@0: struct ShapeHasher {
michael@0:     typedef Shape *Key;
michael@0:     typedef StackShape Lookup;
michael@0: 
michael@0:     static inline HashNumber hash(const Lookup &l);
michael@0:     static inline bool match(Key k, const Lookup &l);
michael@0: };
michael@0: 
michael@0: typedef HashSet<Shape *, ShapeHasher, SystemAllocPolicy> KidsHash;
michael@0: 
michael@0: class KidsPointer {
michael@0:   private:
michael@0:     enum {
michael@0:         SHAPE = 0,
michael@0:         HASH  = 1,
michael@0:         TAG   = 1
michael@0:     };
michael@0: 
michael@0:     uintptr_t w;
michael@0: 
michael@0:   public:
michael@0:     bool isNull() const { return !w; }
michael@0:     void setNull() { w = 0; }
michael@0: 
michael@0:     bool isShape() const { return (w & TAG) == SHAPE && !isNull(); }
michael@0:     Shape *toShape() const {
michael@0:         JS_ASSERT(isShape());
michael@0:         return reinterpret_cast<Shape *>(w & ~uintptr_t(TAG));
michael@0:     }
michael@0:     void setShape(Shape *shape) {
michael@0:         JS_ASSERT(shape);
michael@0:         JS_ASSERT((reinterpret_cast<uintptr_t>(static_cast<Shape *>(shape)) & TAG) == 0);
michael@0:         w = reinterpret_cast<uintptr_t>(static_cast<Shape *>(shape)) | SHAPE;
michael@0:     }
michael@0: 
michael@0:     bool isHash() const { return (w & TAG) == HASH; }
michael@0:     KidsHash *toHash() const {
michael@0:         JS_ASSERT(isHash());
michael@0:         return reinterpret_cast<KidsHash *>(w & ~uintptr_t(TAG));
michael@0:     }
michael@0:     void setHash(KidsHash *hash) {
michael@0:         JS_ASSERT(hash);
michael@0:         JS_ASSERT((reinterpret_cast<uintptr_t>(hash) & TAG) == 0);
michael@0:         w = reinterpret_cast<uintptr_t>(hash) | HASH;
michael@0:     }
michael@0: 
michael@0: #ifdef DEBUG
michael@0:     void checkConsistency(Shape *aKid) const;
michael@0: #endif
michael@0: };
michael@0: 
michael@0: class PropertyTree
michael@0: {
michael@0:     friend class ::JSFunction;
michael@0: 
michael@0:     JSCompartment *compartment_;
michael@0: 
michael@0:     bool insertChild(ExclusiveContext *cx, Shape *parent, Shape *child);
michael@0: 
michael@0:     PropertyTree();
michael@0: 
michael@0:   public:
michael@0:     /*
michael@0:      * Use a lower limit for objects that are accessed using SETELEM (o[x] = y).
michael@0:      * These objects are likely used as hashmaps and dictionary mode is more
michael@0:      * efficient in this case.
michael@0:      */
michael@0:     enum {
michael@0:         MAX_HEIGHT = 512,
michael@0:         MAX_HEIGHT_WITH_ELEMENTS_ACCESS = 128
michael@0:     };
michael@0: 
michael@0:     PropertyTree(JSCompartment *comp)
michael@0:         : compartment_(comp)
michael@0:     {
michael@0:     }
michael@0: 
michael@0:     JSCompartment *compartment() { return compartment_; }
michael@0: 
michael@0:     Shape *newShape(ExclusiveContext *cx);
michael@0:     Shape *getChild(ExclusiveContext *cx, Shape *parent, StackShape &child);
michael@0:     Shape *lookupChild(ThreadSafeContext *cx, Shape *parent, const StackShape &child);
michael@0: };
michael@0: 
michael@0: } /* namespace js */
michael@0: 
michael@0: #endif /* jspropertytree_h */